ip/iplink_vrf.c

   1 /* iplink_vrf.c VRF device support
   2  *
   3  *              This program is free software; you can redistribute it and/or
   4  *              modify it under the terms of the GNU General Public License
   5  *              as published by the Free Software Foundation; either version
   6  *              2 of the License, or (at your option) any later version.
   7  *
   8  * Authors:     Shrijeet Mukherjee <shm@cumulusnetworks.com>
   9  */
  10
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <sys/socket.h>
  15 #include <linux/if_link.h>
  16
  17 #include "rt_names.h"
  18 #include "utils.h"
  19 #include "ip_common.h"
  20
  21 static void vrf_explain(FILE *f)
  22 {
  23         fprintf(f, "Usage: ... vrf table TABLEID\n");
  24 }
  25
  26 static void explain(void)
  27 {
  28         vrf_explain(stderr);
  29 }
  30
  31 static int vrf_parse_opt(struct link_util *lu, int argc, char **argv,
  32                             struct nlmsghdr *n)
  33 {
  34         while (argc > 0) {
  35                 if (matches(*argv, "table") == 0) {
  36                         __u32 table;
  37
  38                         NEXT_ARG();
  39
  40                         if (rtnl_rttable_a2n(&table, *argv))
  41                                 invarg("invalid table ID\n", *argv);
  42                         addattr32(n, 1024, IFLA_VRF_TABLE, table);
  43                 } else if (matches(*argv, "help") == 0) {
  44                         explain();
  45                         return -1;
  46                 } else {
  47                         fprintf(stderr, "vrf: unknown option \"%s\"?\n",
  48                                 *argv);
  49                         explain();
  50                         return -1;
  51                 }
  52                 argc--, argv++;
  53         }
  54
  55         return 0;
  56 }
  57
  58 static void vrf_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
  59 {
  60         if (!tb)
  61                 return;
  62
  63         if (tb[IFLA_VRF_TABLE])
  64                 fprintf(f, "table %u ", rta_getattr_u32(tb[IFLA_VRF_TABLE]));
  65 }
  66
  67 static void vrf_slave_print_opt(struct link_util *lu, FILE *f,
  68                                 struct rtattr *tb[])
  69 {
  70         if (!tb)
  71                 return;
  72
  73         if (tb[IFLA_VRF_PORT_TABLE]) {
  74                 fprintf(f, "table %u ",
  75                         rta_getattr_u32(tb[IFLA_VRF_PORT_TABLE]));
  76         }
  77 }
  78
  79 static void vrf_print_help(struct link_util *lu, int argc, char **argv,
  80                               FILE *f)
  81 {
  82         vrf_explain(f);
  83 }
  84
  85 struct link_util vrf_link_util = {
  86         .id             = "vrf",
  87         .maxattr        = IFLA_VRF_MAX,
  88         .parse_opt      = vrf_parse_opt,
  89         .print_opt      = vrf_print_opt,
  90         .print_help     = vrf_print_help,
  91 };
  92
  93 struct link_util vrf_slave_link_util = {
  94         .id             = "vrf_slave",
  95         .maxattr        = IFLA_VRF_PORT_MAX,
  96         .print_opt      = vrf_slave_print_opt,
  97 };
  98
  99 /* returns table id if name is a VRF device */
 100 __u32 ipvrf_get_table(const char *name)
 101 {
 102         struct {
 103                 struct nlmsghdr         n;
 104                 struct ifinfomsg        i;
 105                 char                    buf[1024];
 106         } req = {
 107                 .n = {
 108                         .nlmsg_len   = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
 109                         .nlmsg_flags = NLM_F_REQUEST,
 110                         .nlmsg_type  = RTM_GETLINK,
 111                 },
 112                 .i = {
 113                         .ifi_family  = preferred_family,
 114                 },
 115         };
 116         struct {
 117                 struct nlmsghdr n;
 118                 char buf[8192];
 119         } answer;
 120         struct rtattr *tb[IFLA_MAX+1];
 121         struct rtattr *li[IFLA_INFO_MAX+1];
 122         struct rtattr *vrf_attr[IFLA_VRF_MAX + 1];
 123         struct ifinfomsg *ifi;
 124         __u32 tb_id = 0;
 125         int len;
 126
 127         addattr_l(&req.n, sizeof(req), IFLA_IFNAME, name, strlen(name) + 1);
 128
 129         if (rtnl_talk(&rth, &req.n, &answer.n, sizeof(answer)) < 0)
 130                 return 0;
 131
 132         ifi = NLMSG_DATA(&answer.n);
 133         len = answer.n.nlmsg_len - NLMSG_LENGTH(sizeof(*ifi));
 134         if (len < 0) {
 135                 fprintf(stderr, "BUG: Invalid response to link query.\n");
 136                 return 0;
 137         }
 138
 139         parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len);
 140
 141         if (!tb[IFLA_LINKINFO])
 142                 return 0;
 143
 144         parse_rtattr_nested(li, IFLA_INFO_MAX, tb[IFLA_LINKINFO]);
 145
 146         if (!li[IFLA_INFO_KIND] || !li[IFLA_INFO_DATA])
 147                 return 0;
 148
 149         if (strcmp(RTA_DATA(li[IFLA_INFO_KIND]), "vrf"))
 150                 return 0;
 151
 152         parse_rtattr_nested(vrf_attr, IFLA_VRF_MAX, li[IFLA_INFO_DATA]);
 153         if (vrf_attr[IFLA_VRF_TABLE])
 154                 tb_id = rta_getattr_u32(vrf_attr[IFLA_VRF_TABLE]);
 155
 156         if (!tb_id)
 157                 fprintf(stderr, "BUG: VRF %s is missing table id\n", name);
 158
 159         return tb_id;
 160 }
 161
 162 bool name_is_vrf(const char *name)
 163 {
 164         struct {
 165                 struct nlmsghdr         n;
 166                 struct ifinfomsg        i;
 167                 char                    buf[1024];
 168         } req = {
 169                 .n = {
 170                         .nlmsg_len   = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
 171                         .nlmsg_flags = NLM_F_REQUEST,
 172                         .nlmsg_type  = RTM_GETLINK,
 173                 },
 174                 .i = {
 175                         .ifi_family  = preferred_family,
 176                 },
 177         };
 178         struct {
 179                 struct nlmsghdr n;
 180                 char buf[8192];
 181         } answer;
 182         struct rtattr *tb[IFLA_MAX+1];
 183         struct rtattr *li[IFLA_INFO_MAX+1];
 184         struct ifinfomsg *ifi;
 185         int len;
 186
 187         addattr_l(&req.n, sizeof(req), IFLA_IFNAME, name, strlen(name) + 1);
 188
 189         if (rtnl_talk(&rth, &req.n, &answer.n, sizeof(answer)) < 0)
 190                 return false;
 191
 192         ifi = NLMSG_DATA(&answer.n);
 193         len = answer.n.nlmsg_len - NLMSG_LENGTH(sizeof(*ifi));
 194         if (len < 0) {
 195                 fprintf(stderr, "BUG: Invalid response to link query.\n");
 196                 return false;
 197         }
 198
 199         parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len);
 200
 201         if (!tb[IFLA_LINKINFO])
 202                 return false;
 203
 204         parse_rtattr_nested(li, IFLA_INFO_MAX, tb[IFLA_LINKINFO]);
 205
 206         if (!li[IFLA_INFO_KIND])
 207                 return false;
 208
 209         return strcmp(RTA_DATA(li[IFLA_INFO_KIND]), "vrf") == 0;
 210 }